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This experiment evaluated the utilization of the recently identified Brazilian giant bamboo, Guaduamagna (Londoño & Filg.) to manufacture medium density particleboard. Four board types were tested:two of them exclusively with particles of bamboo and two in a mixture of bamboo with Pinus taedawood particles. The target density of the panels was 0.65 g/cm3 for all treatments. The particleboardswere bonded using 8% content of urea-formaldehyde (UF) and phenol-formaldehyde (PF) resins, basedon dry weight mat. Mechanical, physical and nondestructive properties of the panels were assessed.The particleboards produced with PF showed better dimensional stability than UF particleboards. Theaddition of wood particles improved the mechanical properties of EM, fM and IB. The flexural propertiesof the panels (EM, fM) could be modeled using either EMd or density and the models fitted presented highpredictability (>66%).

The objective of this research was to determine the physical and mechanical properties of oriented strandboard (OSB) using strands of Cupressus glauca Lam., before and after a thermal treatment, as well as to evaluate the susceptibility of the boards to fungi attack. Boards with nominal density of 0.70 g/cm3 were produced with 5% and 8% of urea-formaldehyde (UF) resin. Physical and mechanical properties were evaluated according to ASTM D 1037 (1991) standard and compared with CSA O437.0 and ANSI A.208.1 standards. All mechanical properties were higher than those values required by both standards, except the modulus of elasticity in parallel axis. The thermal treatment slightly reduced the modulus of elasticity and stress at proportional limit, both in perpendicular axis, however improved significantly dimensional stability. Dimensional stability of the treated OSB was improved at the lower resin level but did not reach the maximum value required by the Canadian standard. Biological assay showed that heat-treated cypress OSB exposed to P. sanguineus reduced mass loss from 39% to 50%, while for G. trabeum the reduction was from 40% to 49%. Post thermal treatment of manufactured OSB (190ºC, 720 s) can be the recommended method to reduce the hygroscopicity without great effect on mechanical properties and to protect panels against these fungi.